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31.
Gupta Kapil Kumar Nath Baikunth Kotagiri Ramamohanarao 《Dependable and Secure Computing, IEEE Transactions on》2010,7(1):35-49
Intrusion detection faces a number of challenges; an intrusion detection system must reliably detect malicious activities in a network and must perform efficiently to cope with the large amount of network traffic. In this paper, we address these two issues of Accuracy and Efficiency using Conditional Random Fields and Layered Approach. We demonstrate that high attack detection accuracy can be achieved by using Conditional Random Fields and high efficiency by implementing the Layered Approach. Experimental results on the benchmark KDD '99 intrusion data set show that our proposed system based on Layered Conditional Random Fields outperforms other well-known methods such as the decision trees and the naive Bayes. The improvement in attack detection accuracy is very high, particularly, for the U2R attacks (34.8 percent improvement) and the R2L attacks (34.5 percent improvement). Statistical Tests also demonstrate higher confidence in detection accuracy for our method. Finally, we show that our system is robust and is able to handle noisy data without compromising performance. 相似文献
32.
This work‐in‐process literature review gives an overview of recent insight in the incorporation of social media in risk and crisis communication. By marrying literature and examples of social media use with best practices in risk and crisis communication, this study demonstrates how communicators can embrace social media tools to better manage a risk or crisis. Best practices in risk and crisis communication are summarized, examples of social media tools used to manage risks and crises are expounded, and recommendations for practitioners are provided to incorporate social media tools in risk and crisis communication. 相似文献
33.
S. Nath 《Computer Physics Communications》2009,180(11):2392-2393
34.
Multimedia Tools and Applications - Identification and authentication are ubiquitous questions which pan across various systems. In certain domains, they are of paramount importance. Like, security... 相似文献
35.
The body of a walking human is an elaborated dynamic system that operates adaptively in various conditions such as fast walking. Due to dynamic redundancies, the individual motor control strategies for speeding up the walking can be different among normal subjects. However, in reality, we see that the pattern of motion is quite similar among people and it is only the profile of hip joint motion along its path which determines the speed. The objective of the current paper is to develop a mathematical framework to investigate time optimal motion of a human during walking. To this end, a nine-link planar biped model is used. The motion is considered to take place in sagittal plane and to follow a normal pattern of motion. The solution is obtained using a phase plane method to solve minimum time problem which is subjected to inequality constraints of variable maximum joint torques and stability conditions. The solution method can be used to find the maximum possible speed of a human with specific body characteristics and to obtain a hip joint trajectory which could produce that speed. The proposed method can be utilized to study quantitative effect of different parameters such as joint strength in fast walking. 相似文献
36.
Tara Matthews Steve Whittaker Thomas P. Moran Sandra Y. Helsley Tejinder K. Judge 《Computer Supported Cooperative Work (CSCW)》2012,21(4-5):371-396
Work organization and team membership is highly complex for modern workers. Teams are often dynamic as personnel change during a project. Dynamic team members have to be actively recruited and personnel changes make it harder for participants to retain group focus. Workers are often members of multiple groups. Though prior work has identified the prevalence of multi-teaming and dynamic teams, it has been unable to explain how workers cope with the challenges the new style of work should cause. This paper systematically characterizes the modern organizational landscape from an individual perspective, by studying how people typically organize work across their multiple collaborative groups. A unique contribution of our work is to examine the interrelationships between the collaborative groups individuals typically participate in. We introduce the notion of a collaboration profile to characterize these interrelations. We expected workers to be overburdened by contributing to multiple teams often with shifting personnel. However, we found that multi-teaming involves productive interrelationships between collaborative groups that ease some of the documented challenges of dynamic teams, such as goal setting, recruiting, and group maintenance. We define a typology that describes the various types of collaborative groups workers participate in, and provide examples of productive interrelations between collaborations. In characterizing interrelations between collaborations, we provide detailed examples of how people exploit resources across their different collaborations to address the problems of working in multiple dynamic teams. 相似文献
37.
Mahendra Nath Roy Bhoj Bahadur Gurung Vikas Kumar Dakua 《International Journal of Thermophysics》2006,27(5):1539-1550
Electrolytic conductivities of potassium halides, KX (X = Cl−, Br−, I−) have been investigated in 10, 20, and 30 mass% glycerol + H2O mixtures at 298.0, 308.0, and 318.0 K. The conductance data have been analyzed by the Fuoss-conductance–concentration equation in terms of the limiting molar conductance (Λ0), the association constant (K
A
), and the distance of closest approach of ion (R). The association constant (K
A
) tends to increase in the order: 10 mass% < 20 mass% < 30 mass% glycerol + water mixtures, while it decreases with temperature. Thermodynamic parameters ΔH
0, ΔG
0, and ΔS
0 are obtained and discussed. Also, Walden products (Λ0η) are reported. The results have been interpreted in terms of ion–solvent interactions and structural changes in the mixed solvents. 相似文献
38.
Lacreuse Agnès; Kim Charles B.; Rosene Douglas L.; Killiany Ronald J.; Moss Mark B.; Moore Tara L.; Chennareddi Lakshmi; Herndon James G. 《Canadian Metallurgical Quarterly》2005,119(1):118
The authors tested 90 rhesus monkeys (Macaca mulatta) on a task of spatial memory, the spatial Delayed Recognition Span Test. The results showed that performance declined significantly with age, males had greater scores than females, and the rate of apparent decline with age was greater in males than in females. Both working and reference memory declined with age, but only working memory showed sex differences. The authors compared these data with that of 22 monkeys who were trained on a simpler version of the task before formal testing. Training had no effect on males but dramatically improved working memory in young females. The results confirm a male advantage in spatial working memory at a young age and confirm a greater decline with age in males than in females. It is important to note that prior training completely reverses the deficits of young females. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
39.
Reviews the book Protecting children from domestic violence: Strategies for community intervention, edited by Peter J. Jaffe, Linda L. Baker, and Alison J. Cunningham (see record 2005-04430-000). The book emerged from the International Conference on Children Exposed to Domestic Violence that was held in London, Ontario in 2001. It begins with an excellent chapter by Jeffrey Edleson synthesizing the literature on the impact of exposure to domestic violence on children. Edleson's chapter is followed by two papers examining emerging assessments and treatment programs. The second section of the book addresses current thinking about individual and group intervention approaches. The third section of the book examines broader system level responses, including public awareness and school-based campaigns, as well as responses by the courts and police. This is a well-organized collection of papers that provides a good overview of the state of knowledge and innovative practice in an emerging field of practice. Protecting Children from Domestic Violence provides practitioners, policy makers, and researchers with an excellent overview of current knowledge and practices in working with children exposed to domestic violence. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
40.
This paper focuses on the promise of globally linearized control (GLC) structure in the realm of strongly nonlinear reactor system control. The proposed nonlinear control strategy is comprised of: (i) an input-output linearizing state feedback law (transformer), (ii) a state observer, and (iii) an external linear controller. The synthesis of discrete-time GLC controller for single-input single-output diabatic continuous stirred tank reactor (DCSTR) has been studied first, followed by the synthesis of feedforward/feedback controller for the same reactor having dead time in process as well as in disturbance. Subsequently, the multivariable GLC structure has been designed and then applied on multi-input multi-output DCSTR system. The simulation study shows high quality performance of the derived nonlinear controllers. The better-performed GLC in conjunction with reduced-order observer has been compared with the conventional proportional integral controller on the example reactor and superior performance has been achieved by the proposed GLC control scheme. 相似文献